<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        div{
            height: 50px;
        }
    </style>
</head>
<body>
    <div class="" style="width: 100%;position: relative;">
        <div style="position:absolute;z-index:-100;background-color: #ffaa00;width: 100%;"></div>
        <div style="position: absolute;z-index: 100;">1212</div>
    </div>
</body>
</html>